Petraeus tells congress he regrets affair

EX-CIA director David Petraeus has expressed deep regret over the affair that led to his resignation but insisted it did not interfere with his work on the Benghazi attack, legislators say.

"The general did not address any specifics of the affair," Democratic congressman James Langevin said as he emerged from a House Intelligence Committee hearing that heard testimony from Petraeus.

"What he did say in his opening statement was that he deeply regrets the circumstances that led to his resignation," he said, referring to the revelation that Petraeus had an extramarital affair with his biographer Paula Broadwell.

Petraeus's departure has sent shockwaves through Washington, where lawmakers are hosting several closed-door intelligence briefings on a September 11 attack on the US mission in Benghazi, Libya that cost four Americans their lives.

Petraeus spoke at two of the hearings on Friday but avoided the media packs staking out both the House and Senate.

Republican Peter King said there was a single question in the House hearing about the Broadwell affair, addressing whether it had any impact on Petraeus's testimony "and he said no".

Democrat lawmaker Dutch Ruppersberger agreed.

"He was very sorry that this incident occurred, and anything that occurred with respect to his personal situation had nothing to do with the way he handled Benghazi at all," the Maryland congressman said.

"And he also clarified ... that his resignation wasn't because he didn't want to testify. Clearly that was not the case. End of story."

King, who chairs the House Homeland Security Committee, acknowledged the awkwardness of essentially interrogating a friend whom he has known for nearly a decade and once urged to run for president.

"I consider him a friend, which made the questioning tough, to be honest with you," King told reporters.

"You realised that he's going through an awful lot. On the other hand, we had an obligation to find out what we could."

Petraeus was CIA chief during the September attack and travelled to Libya in the aftermath. Lawmakers were eager to hear his on-the-ground assessment, as well as his take on security operations at the US mission in Benghazi.